The present invention relates generally to weightlifting and barbell devices used therein, and more particularly provides a unique apparatus for retaining weights on such a barbell device.
As is well known, barbells used in the sport of weight lifting are provided with disc-shaped weights that can be mounted alone or in combination on the end of a bar, to allow the user to vary the weight he lifts during his workout. These weight discs have holes through their centers to allow the bar to be inserted through the discs. Various types of collars can be placed on the bar between the outermost weight disc and the end of the bar, to secure the weight discs on the bar.
In order for the sport of weight lifting to be practiced safely, it is desirable for the collar to be secure. Without proper security, a weight disc may become dislodged, and/or the barbell may become imbalanced, and cause injury to the weight lifter or to bystanders.
In order for the sport of weightlifting to be practiced conveniently, it is desirable that the collar be quickly and easily removed. This allows the weight lifter to vary the load on the barbell with a minimum interruption of time and/or interruption in the weightlifter's mental concentration.
In general, prior art collars that are secure and have desirable safety characteristics are not convenient to use, in that they are not easily and quickly removable. Furthermore, prior art collars or other types of weight disc retaining devices generally have a relatively fixed amount of frictional force holding them in place on the bar; that is, the amount of frictional force with which the collar is initially loaded does not change during the weight lifting exercise. The "safety" of the aforementioned prior art is therefore "fixed" in comparison to the present invention, whose "safety" may increase during a lift due to increased frictional gripping of the apparatus onto the bar, as more fully described below. Examples of such devices are set forth in U.S. Pat. Nos. 4,639,979; 3,305,234; 4,569,105; 4,646,398; and 3,726,522.
It is accordingly an object of the present invention to provide improved apparatus for retaining weights on barbells which, compared to conventional retaining devices, is both safer and more convenient to use.